diff --git a/CHANGES b/CHANGES
index f9f267c3a90..0e03a3f0a13 100644
--- a/CHANGES
+++ b/CHANGES
@@ -77,6 +77,8 @@ Bugs fixed
   with size explicitly set in pixels) (fixed for ``'pdflatex'/'lualatex'`` only)
 * #8911: C++: remove the longest matching prefix in
   :confval:`cpp_index_common_prefix` instead of the first that matches.
+* C, properly reject function declarations when a keyword is used
+  as parameter name.
 
 Testing
 --------
diff --git a/sphinx/domains/c.py b/sphinx/domains/c.py
index 061010d6651..458467e6abc 100644
--- a/sphinx/domains/c.py
+++ b/sphinx/domains/c.py
@@ -9,8 +9,8 @@
 """
 
 import re
-from typing import (Any, Callable, Dict, Generator, Iterator, List, Tuple, Type, TypeVar,
-                    Union, cast)
+from typing import (Any, Callable, Dict, Generator, Iterator, List, Optional, Tuple, Type,
+                    TypeVar, Union, cast)
 
 from docutils import nodes
 from docutils.nodes import Element, Node, TextElement, system_message
@@ -78,8 +78,8 @@
 _expression_assignment_ops = ["=", "*=", "/=", "%=", "+=", "-=",
                               ">>=", "<<=", "&=", "and_eq", "^=", "xor_eq", "|=", "or_eq"]
 
-_max_id = 1
-_id_prefix = [None, 'c.', 'Cv2.']
+_max_id = 2
+_id_prefix = [None, 'c.', 'C2-']
 # Ids are used in lookup keys which are used across pickled files,
 # so when _max_id changes, make sure to update the ENV_VERSION.
 
@@ -108,31 +108,59 @@ def describe_signature(self, signode: TextElement, mode: str,
 ################################################################################
 
 class ASTIdentifier(ASTBaseBase):
-    def __init__(self, identifier: str) -> None:
+    def __init__(self, identifier: str, tag: Optional[str]) -> None:
+        # tag:
+        # - len > 0: it's a struct/union/enum
+        # - len == 0: it's not a struct/union/enum
+        # - None: for matching, can be either
         assert identifier is not None
         assert len(identifier) != 0
         self.identifier = identifier
-
-    def __eq__(self, other: Any) -> bool:
-        return type(other) is ASTIdentifier and self.identifier == other.identifier
+        self.tag = tag
 
     def is_anon(self) -> bool:
         return self.identifier[0] == '@'
 
+    def get_id(self, version: int) -> str:
+        if version <= 1:
+            return self.identifier
+        if self.tag:
+            assert len(self.tag) != 0
+            return '-' + self.identifier
+        else:
+            return self.identifier
+
+    def matches(self, other: "ASTIdentifier") -> bool:
+        if self.identifier != other.identifier:
+            return False
+        if self.tag is None:
+            return True
+        assert other.tag is not None
+        isTag = self.tag == ''
+        isOtherTag = other.tag == ''
+        return isTag == isOtherTag
+
     # and this is where we finally make a difference between __str__ and the display string
 
     def __str__(self) -> str:
-        return self.identifier
+        return self.tag + " " + self.identifier if self.tag else self.identifier
 
     def get_display_string(self) -> str:
-        return "[anonymous]" if self.is_anon() else self.identifier
+        id = "[anonymous]" if self.is_anon() else self.identifier
+        return self.tag + " " + id if self.tag else id
 
     def describe_signature(self, signode: TextElement, mode: str, env: "BuildEnvironment",
                            prefix: str, symbol: "Symbol") -> None:
         # note: slightly different signature of describe_signature due to the prefix
         verify_description_mode(mode)
+        if self.tag:
+            signode += nodes.Text(self.tag)
+            signode += nodes.Text(' ')
         if mode == 'markType':
-            targetText = prefix + self.identifier
+            if self.tag:
+                targetText = prefix + self.tag + ' ' + self.identifier
+            else:
+                targetText = prefix + self.identifier
             pnode = addnodes.pending_xref('', refdomain='c',
                                           reftype='identifier',
                                           reftarget=targetText, modname=None,
@@ -163,12 +191,17 @@ def __init__(self, names: List[ASTIdentifier], rooted: bool) -> None:
         self.names = names
         self.rooted = rooted
 
+    def setTagsToPattern(self) -> None:
+        for n in self.names:
+            if n.tag == '':
+                n.tag = None
+
     @property
     def name(self) -> "ASTNestedName":
         return self
 
     def get_id(self, version: int) -> str:
-        return '.'.join(str(n) for n in self.names)
+        return '.'.join(n.get_id(version) for n in self.names)
 
     def _stringify(self, transform: StringifyTransform) -> str:
         res = '.'.join(transform(n) for n in self.names)
@@ -387,19 +420,6 @@ def describe_signature(self, signode: TextElement, mode: str,
         signode.append(nodes.Text('--'))
 
 
-class ASTPostfixMember(ASTPostfixOp):
-    def __init__(self, name):
-        self.name = name
-
-    def _stringify(self, transform: StringifyTransform) -> str:
-        return '.' + transform(self.name)
-
-    def describe_signature(self, signode: TextElement, mode: str,
-                           env: "BuildEnvironment", symbol: "Symbol") -> None:
-        signode.append(nodes.Text('.'))
-        self.name.describe_signature(signode, 'noneIsName', env, symbol)
-
-
 class ASTPostfixMemberOfPointer(ASTPostfixOp):
     def __init__(self, name):
         self.name = name
@@ -607,8 +627,7 @@ def describe_signature(self, signode: TextElement, mode: str,
 
 
 class ASTTrailingTypeSpecName(ASTTrailingTypeSpec):
-    def __init__(self, prefix: str, nestedName: ASTNestedName) -> None:
-        self.prefix = prefix
+    def __init__(self, nestedName: ASTNestedName) -> None:
         self.nestedName = nestedName
 
     @property
@@ -616,18 +635,10 @@ def name(self) -> ASTNestedName:
         return self.nestedName
 
     def _stringify(self, transform: StringifyTransform) -> str:
-        res = []
-        if self.prefix:
-            res.append(self.prefix)
-            res.append(' ')
-        res.append(transform(self.nestedName))
-        return ''.join(res)
+        return transform(self.nestedName)
 
     def describe_signature(self, signode: TextElement, mode: str,
                            env: "BuildEnvironment", symbol: "Symbol") -> None:
-        if self.prefix:
-            signode += addnodes.desc_annotation(self.prefix, self.prefix)
-            signode += nodes.Text(' ')
         self.nestedName.describe_signature(signode, mode, env, symbol=symbol)
 
 
@@ -1678,7 +1689,7 @@ def candidates() -> Generator["Symbol", None, None]:
             if Symbol.debug_lookup:
                 Symbol.debug_print("candidate:")
                 print(s.to_string(Symbol.debug_indent + 1), end="")
-            if s.ident == ident:
+            if s.ident and ident.matches(s.ident):
                 if Symbol.debug_lookup:
                     Symbol.debug_indent += 1
                     Symbol.debug_print("matches")
@@ -1875,23 +1886,9 @@ def handleDuplicateDeclaration(symbol: "Symbol", candSymbol: "Symbol") -> None:
                 candSymbol.isRedeclaration = True
                 raise _DuplicateSymbolError(symbol, declaration)
 
-            if declaration.objectType != "function":
-                assert len(withDecl) <= 1
-                handleDuplicateDeclaration(withDecl[0], candSymbol)
-                # (not reachable)
-
-            # a function, so compare IDs
-            candId = declaration.get_newest_id()
-            if Symbol.debug_lookup:
-                Symbol.debug_print("candId:", candId)
-            for symbol in withDecl:
-                oldId = symbol.declaration.get_newest_id()
-                if Symbol.debug_lookup:
-                    Symbol.debug_print("oldId: ", oldId)
-                if candId == oldId:
-                    handleDuplicateDeclaration(symbol, candSymbol)
-                    # (not reachable)
-            # no candidate symbol found with matching ID
+            assert len(withDecl) <= 1
+            handleDuplicateDeclaration(withDecl[0], candSymbol)
+            # (not reachable)
         # if there is an empty symbol, fill that one
         if len(noDecl) == 0:
             if Symbol.debug_lookup:
@@ -1973,8 +1970,12 @@ def add_declaration(self, declaration: ASTDeclaration,
             Symbol.debug_print("add_declaration:")
         assert declaration is not None
         assert docname is not None
-        assert line is not None
-        nestedName = declaration.name
+        assert declaration.name.names[-1].tag == ''
+        if declaration.objectType in ('struct', 'union', 'enum'):
+            nestedName = declaration.name.clone()
+            nestedName.names[-1].tag = declaration.objectType
+        else:
+            nestedName = declaration.name
         res = self._add_symbols(nestedName, declaration, docname, line)
         if Symbol.debug_lookup:
             Symbol.debug_indent -= 1
@@ -2000,11 +2001,11 @@ def find_identifier(self, ident: ASTIdentifier,
                 Symbol.debug_print("trying:")
                 print(current.to_string(Symbol.debug_indent + 1), end="")
                 Symbol.debug_indent -= 2
-            if matchSelf and current.ident == ident:
+            if matchSelf and ident.matches(current.ident):
                 return current
             children = current.children_recurse_anon if recurseInAnon else current._children
             for s in children:
-                if s.ident == ident:
+                if ident.matches(s.ident):
                     return s
             if not searchInSiblings:
                 break
@@ -2102,8 +2103,6 @@ class DefinitionParser(BaseParser):
         '__int64',
     )
 
-    _prefix_keys = ('struct', 'enum', 'union')
-
     @property
     def language(self) -> str:
         return 'C'
@@ -2195,10 +2194,9 @@ def _parse_primary_expression(self) -> ASTExpression:
         res = self._parse_paren_expression()
         if res is not None:
             return res
-        nn = self._parse_nested_name()
-        if nn is not None:
-            return ASTIdExpression(nn)
-        return None
+        nn = self._parse_nested_name(allowTags=None)
+        assert nn is not None
+        return ASTIdExpression(nn)
 
     def _parse_initializer_list(self, name: str, open: str, close: str
                                 ) -> Tuple[List[ASTExpression], bool]:
@@ -2256,7 +2254,7 @@ def _parse_postfix_expression(self) -> ASTPostfixExpr:
         #  | postfix "[" expression "]"
         #  | postfix "[" braced-init-list [opt] "]"
         #  | postfix "(" expression-list [opt] ")"
-        #  | postfix "." id-expression
+        #  | postfix "." id-expression  // taken care of in primary by nested name
         #  | postfix "->" id-expression
         #  | postfix "++"
         #  | postfix "--"
@@ -2274,23 +2272,12 @@ def _parse_postfix_expression(self) -> ASTPostfixExpr:
                     self.fail("Expected ']' in end of postfix expression.")
                 postFixes.append(ASTPostfixArray(expr))
                 continue
-            if self.skip_string('.'):
-                if self.skip_string('*'):
-                    # don't steal the dot
-                    self.pos -= 2
-                elif self.skip_string('..'):
-                    # don't steal the dot
-                    self.pos -= 3
-                else:
-                    name = self._parse_nested_name()
-                    postFixes.append(ASTPostfixMember(name))
-                    continue
             if self.skip_string('->'):
                 if self.skip_string('*'):
                     # don't steal the arrow
                     self.pos -= 3
                 else:
-                    name = self._parse_nested_name()
+                    name = self._parse_nested_name(allowTags=None)
                     postFixes.append(ASTPostfixMemberOfPointer(name))
                     continue
             if self.skip_string('++'):
@@ -2508,15 +2495,26 @@ def _parse_expression_fallback(
             value = self.definition[startPos:self.pos].strip()
         return ASTFallbackExpr(value.strip())
 
-    def _parse_nested_name(self) -> ASTNestedName:
-        names = []  # type: List[Any]
+    def _parse_nested_name(self, *, allowTags: Optional[str] = 'not last') -> ASTNestedName:
+        # A dot-separated list of identifiers, each with an optional struct/union/enum tag.
+        # A leading dot makes the name rooted at global scope.
+
+        assert allowTags in (None, 'all', 'not last')
+
+        names = []  # type: List[ASTIdentifier]
 
-        self.skip_ws()
         rooted = False
         if self.skip_string('.'):
             rooted = True
         while 1:
             self.skip_ws()
+            tag = ''
+            if allowTags is not None:
+                for k in ('struct', 'union', 'enum'):
+                    if self.skip_word_and_ws(k):
+                        tag = k
+                        break
+            afterTagPos = self.pos
             if not self.match(identifier_re):
                 self.fail("Expected identifier in nested name.")
             identifier = self.matched_text
@@ -2524,13 +2522,19 @@ def _parse_nested_name(self) -> ASTNestedName:
             if identifier in _keywords:
                 self.fail("Expected identifier in nested name, "
                           "got keyword: %s" % identifier)
-            ident = ASTIdentifier(identifier)
+            ident = ASTIdentifier(identifier, tag)
             names.append(ident)
 
             self.skip_ws()
             if not self.skip_string('.'):
                 break
-        return ASTNestedName(names, rooted)
+
+        # post hax to explicitly forbid the last one to have a tag
+        if allowTags == 'not last' and names[-1].tag != '':
+            self.pos = afterTagPos
+            self.fail("Expected identifier in nested name, "
+                      "got keyword: %s" % names[-1].tag)
+        return ASTNestedName(names, rooted=rooted)
 
     def _parse_trailing_type_spec(self) -> ASTTrailingTypeSpec:
         # fundamental types
@@ -2563,16 +2567,8 @@ def _parse_trailing_type_spec(self) -> ASTTrailingTypeSpec:
         if len(elements) > 0:
             return ASTTrailingTypeSpecFundamental(' '.join(elements))
 
-        # prefixed
-        prefix = None
-        self.skip_ws()
-        for k in self._prefix_keys:
-            if self.skip_word_and_ws(k):
-                prefix = k
-                break
-
-        nestedName = self._parse_nested_name()
-        return ASTTrailingTypeSpecName(prefix, nestedName)
+        nestedName = self._parse_nested_name(allowTags='all')
+        return ASTTrailingTypeSpecName(nestedName)
 
     def _parse_parameters(self, paramMode: str) -> ASTParameters:
         self.skip_ws()
@@ -2693,17 +2689,14 @@ def _parse_decl_specs(self, outer: str, typed: bool = True) -> ASTDeclSpecs:
     def _parse_declarator_name_suffix(
             self, named: Union[bool, str], paramMode: str, typed: bool
     ) -> ASTDeclarator:
+        assert named in (True, False, 'single')
         # now we should parse the name, and then suffixes
-        if named == 'maybe':
-            pos = self.pos
-            try:
-                declId = self._parse_nested_name()
-            except DefinitionError:
-                self.pos = pos
-                declId = None
-        elif named == 'single':
+        if named == 'single':
             if self.match(identifier_re):
-                identifier = ASTIdentifier(self.matched_text)
+                if self.matched_text in _keywords:
+                    self.fail("Expected identifier, "
+                              "got keyword: %s" % self.matched_text)
+                identifier = ASTIdentifier(self.matched_text, '')
                 declId = ASTNestedName([identifier], rooted=False)
             else:
                 declId = None
@@ -2880,8 +2873,8 @@ def parser():
 
     def _parse_type(self, named: Union[bool, str], outer: str = None) -> ASTType:
         """
-        named=False|'maybe'|True: 'maybe' is e.g., for function objects which
-        doesn't need to name the arguments
+        named=False|'single'|True: 'single' is e.g., for function objects which
+        doesn't need to name the arguments, but otherwise is a single name
         """
         if outer:  # always named
             if outer not in ('type', 'member', 'function'):
@@ -2965,7 +2958,7 @@ def _parse_macro(self) -> ASTMacro:
                 break
             if not self.match(identifier_re):
                 self.fail("Expected identifier in macro parameters.")
-            nn = ASTNestedName([ASTIdentifier(self.matched_text)], rooted=False)
+            nn = ASTNestedName([ASTIdentifier(self.matched_text, '')], rooted=False)
             # Allow named variadic args:
             # https://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html
             self.skip_ws()
@@ -3062,10 +3055,10 @@ def parse_declaration(self, objectType: str, directiveType: str) -> ASTDeclarati
         return ASTDeclaration(objectType, directiveType, declaration, semicolon)
 
     def parse_namespace_object(self) -> ASTNestedName:
-        return self._parse_nested_name()
+        return self._parse_nested_name(allowTags='all')
 
     def parse_xref_object(self) -> ASTNestedName:
-        name = self._parse_nested_name()
+        name = self._parse_nested_name(allowTags='all')
         # if there are '()' left, just skip them
         self.skip_ws()
         self.skip_string('()')
@@ -3095,7 +3088,7 @@ def parse_expression(self) -> Union[ASTExpression, ASTType]:
 
 
 def _make_phony_error_name() -> ASTNestedName:
-    return ASTNestedName([ASTIdentifier("PhonyNameDueToError")], rooted=False)
+    return ASTNestedName([ASTIdentifier("PhonyNameDueToError", None)], rooted=False)
 
 
 class CObject(ObjectDescription[ASTDeclaration]):
@@ -3809,6 +3802,11 @@ def _resolve_xref_inner(self, env: BuildEnvironment, fromdocname: str, builder:
             logger.warning('Unparseable C cross-reference: %r\n%s', target, e,
                            location=node)
             return None, None
+        if typ in ('struct', 'union', 'enum'):
+            last = name.names[-1]
+            if last.tag == '':
+                last.tag = typ
+
         parentKey = node.get("c:parent_key", None)  # type: LookupKey
         rootSymbol = self.data['root_symbol']
         if parentKey:
@@ -3820,10 +3818,61 @@ def _resolve_xref_inner(self, env: BuildEnvironment, fromdocname: str, builder:
             assert parentSymbol  # should be there
         else:
             parentSymbol = rootSymbol
+
         s = parentSymbol.find_declaration(name, typ,
                                           matchSelf=True, recurseInAnon=True)
         if s is None or s.declaration is None:
-            return None, None
+            # try with relaxed tagging
+            name.setTagsToPattern()
+            s = parentSymbol.find_declaration(name, typ,
+                                              matchSelf=True, recurseInAnon=True)
+            if s is None or s.declaration is None:
+                return None, None
+            # only warn for identifiers, as they should contain the correct tagging
+            if typ == 'identifier':
+                logger.warning(
+                    "c:%s reference has incorrect tagging:"
+                    " Full reference name is '%s'."
+                    " Full found name is '%s'.",
+                    typ, name, s.get_full_nested_name(), location=node)
+            # TODO: conditionally warn about xrefs with incorrect tagging?
+
+        # check if tags are used correctly
+        sName = s.get_full_nested_name()
+        assert len(name.names) <= len(sName.names)
+        nextName = len(sName.names) - 1
+        # print("Matching '{}' to '{}'".format(name, sName))
+        for xRefName in reversed(name.names):
+            # find the next symbol name that matches the xref name
+            # potentially skipping anon names
+            # print("\tMatching:", xRefName)
+            stop = False
+            while True:
+                if nextName == -1:
+                    stop = True
+                    break
+                ns = sName.names[nextName]
+                nextName -= 1
+                if xRefName.identifier == ns.identifier:
+                    # print("\t\tSame ident:", ns)
+                    break
+                else:
+                    # print("\t\tSkipping:", ns)
+                    assert ns.is_anon()
+            if stop:
+                break
+            # print("\t\tRes(nextName={}): '{}' vs. '{}'".format(nextName, xRefName, ns))
+            if xRefName.tag is None:
+                continue
+            assert ns.tag is not None
+            assert (xRefName.tag == '') == (ns.tag == '')
+            if xRefName.tag != ns.tag:
+                logger.warning(
+                    "c:%s reference uses wrong tag:"
+                    " reference name is '%s' but found name is '%s'."
+                    " Full reference name is '%s'."
+                    " Full found name is '%s'.",
+                    typ, xRefName, ns, name, sName, location=node)
 
         # TODO: check role type vs. object type
 
@@ -3876,9 +3925,18 @@ def setup(app: Sphinx) -> Dict[str, Any]:
     app.add_config_value("c_allow_pre_v3", False, 'env')
     app.add_config_value("c_warn_on_allowed_pre_v3", True, 'env')
 
+    # debug stuff
+    app.add_config_value("c_debug_lookup", False, '')
+    app.add_config_value("c_debug_show_tree", False, '')
+
+    def setDebugFlags(app):
+        Symbol.debug_lookup = app.config.c_debug_lookup
+        Symbol.debug_show_tree = app.config.c_debug_show_tree
+    app.connect("builder-inited", setDebugFlags)
+
     return {
         'version': 'builtin',
-        'env_version': 2,
+        'env_version': 3,
         'parallel_read_safe': True,
         'parallel_write_safe': True,
     }
diff --git a/tests/roots/test-domain-c-intersphinx/index.rst b/tests/roots/test-domain-c-intersphinx/index.rst
index 5d6d3e09891..c97cc695c0e 100644
--- a/tests/roots/test-domain-c-intersphinx/index.rst
+++ b/tests/roots/test-domain-c-intersphinx/index.rst
@@ -60,3 +60,12 @@
 	- :c:member:`_functionParam.param`
 	- :c:var:`_functionParam.param`
 	- :c:data:`_functionParam.param`
+
+- :any:`_struct.@anon.i`
+- :c:member:`_struct.@anon.i`
+- :c:var:`_struct.@anon.i`
+- :c:data:`_struct.@anon.i`
+- :any:`_struct.i`
+- :c:member:`_struct.i`
+- :c:var:`_struct.i`
+- :c:data:`_struct.i`
diff --git a/tests/roots/test-domain-c/anon-dup-decl.rst b/tests/roots/test-domain-c/anon-dup-decl.rst
index 5f6c3bdfe36..743ae2f6a84 100644
--- a/tests/roots/test-domain-c/anon-dup-decl.rst
+++ b/tests/roots/test-domain-c/anon-dup-decl.rst
@@ -1,3 +1,5 @@
+.. c:namespace:: anon_dup_decl_ns
+
 .. c:struct:: anon_dup_decl
 
 	.. c:struct:: @a.A
diff --git a/tests/roots/test-domain-c/function_param_target.rst b/tests/roots/test-domain-c/function_param_target.rst
index 05de01445d4..d316d7bcd16 100644
--- a/tests/roots/test-domain-c/function_param_target.rst
+++ b/tests/roots/test-domain-c/function_param_target.rst
@@ -1,3 +1,5 @@
+.. c:namespace:: function_param_target
+
 .. c:function:: void f(int i)
 
 	- :c:var:`i`
diff --git a/tests/roots/test-domain-c/ids-vs-tags0.rst b/tests/roots/test-domain-c/ids-vs-tags0.rst
new file mode 100644
index 00000000000..f00d3b79570
--- /dev/null
+++ b/tests/roots/test-domain-c/ids-vs-tags0.rst
@@ -0,0 +1,90 @@
+.. c:member:: int _member
+.. c:var:: int _var
+.. c:function:: void _function()
+.. c:macro:: _macro
+.. c:struct:: _struct
+
+	.. c:union:: @anon
+
+		.. c:var:: int i
+
+.. c:union:: _union
+.. c:enum:: _enum
+
+    .. c:enumerator:: _enumerator
+
+.. c:type:: _type
+.. c:function:: void _functionParam(int param)
+
+
+.. c:member:: void __member = _member
+
+	- :any:`_member`
+	- :c:member:`_member`
+	- :c:var:`_member`
+	- :c:data:`_member`
+
+.. c:member:: void __var = _var
+
+	- :any:`_var`
+	- :c:member:`_var`
+	- :c:var:`_var`
+	- :c:data:`_var`
+
+.. c:member:: void __function = _function
+
+	- :any:`_function`
+	- :c:func:`_function`
+	- :c:type:`_function`
+
+.. c:member:: void __macro = _macro
+
+	- :any:`_macro`
+	- :c:macro:`_macro`
+
+.. c:type:: _struct __struct
+            struct _struct __structTagged
+
+	- :any:`_struct`
+	- :c:struct:`_struct`
+	- :c:type:`_struct`
+
+.. c:type:: _union __union
+            union _union __unionTagged
+
+	- :any:`_union`
+	- :c:union:`_union`
+	- :c:type:`_union`
+
+.. c:type:: _enum __enum
+            enum _enum __enumTagged
+
+	- :any:`_enum`
+	- :c:enum:`_enum`
+	- :c:type:`_enum`
+
+.. c:member:: void __enumerator = _enumerator
+
+	- :any:`_enumerator`
+	- :c:enumerator:`_enumerator`
+
+.. c:type:: _type __type
+
+	- :any:`_type`
+	- :c:type:`_type`
+
+.. c:member:: void __functionParam = _functionParam.param
+
+	- :any:`_functionParam.param`
+	- :c:member:`_functionParam.param`
+	- :c:var:`_functionParam.param`
+	- :c:data:`_functionParam.param`
+
+- :any:`_struct.@anon.i`
+- :c:member:`_struct.@anon.i`
+- :c:var:`_struct.@anon.i`
+- :c:data:`_struct.@anon.i`
+- :any:`_struct.i`
+- :c:member:`_struct.i`
+- :c:var:`_struct.i`
+- :c:data:`_struct.i`
diff --git a/tests/roots/test-domain-c/ids-vs-tags1.rst b/tests/roots/test-domain-c/ids-vs-tags1.rst
new file mode 100644
index 00000000000..177722dcd40
--- /dev/null
+++ b/tests/roots/test-domain-c/ids-vs-tags1.rst
@@ -0,0 +1,27 @@
+.. c:namespace:: ids_vs_tags
+
+.. c:struct:: f_struct
+.. c:type:: struct f_struct f_struct
+.. c:union:: f_union
+.. c:type:: union f_union f_union
+.. c:enum:: f_enum
+.. c:type:: enum f_enum f_enum
+
+- :c:struct:`f_struct`
+- :c:struct:`struct f_struct`
+- :c:type:`f_struct`
+- :c:type:`struct f_struct`
+- :any:`f_struct`
+- :any:`struct f_struct`
+- :c:union:`f_union`
+- :c:union:`union f_union`
+- :c:type:`f_union`
+- :c:type:`union f_union`
+- :any:`f_union`
+- :any:`union f_union`
+- :c:enum:`f_enum`
+- :c:enum:`enum f_enum`
+- :c:type:`f_enum`
+- :c:type:`enum f_enum`
+- :any:`f_enum`
+- :any:`enum f_enum`
diff --git a/tests/roots/test-domain-c/ids-vs-tags2.rst b/tests/roots/test-domain-c/ids-vs-tags2.rst
new file mode 100644
index 00000000000..822ae583b52
--- /dev/null
+++ b/tests/roots/test-domain-c/ids-vs-tags2.rst
@@ -0,0 +1,22 @@
+.. c:namespace:: ids_vs_tags2
+
+.. c:struct:: A
+
+   .. c:union:: @B
+
+      .. c:enum:: C
+
+         .. c:enumerator:: D
+
+- :c:enumerator:`struct A.union @B.enum C.D`
+- :c:enumerator:`A.union @B.enum C.D`
+- :c:enumerator:`struct A.@B.enum C.D`
+- :c:enumerator:`struct A.union @B.C.D`
+- :c:enumerator:`A.@B.enum C.D`
+- :c:enumerator:`A.union @B.C.D`
+- :c:enumerator:`struct A.@B.C.D`
+- :c:enumerator:`A.@B.C.D`
+- :c:enumerator:`struct A.enum C.D`
+- :c:enumerator:`A.enum C.D`
+- :c:enumerator:`struct A.C.D`
+- :c:enumerator:`A.C.D`
diff --git a/tests/roots/test-domain-c/ids-vs-tags3.rst b/tests/roots/test-domain-c/ids-vs-tags3.rst
new file mode 100644
index 00000000000..50d90506e22
--- /dev/null
+++ b/tests/roots/test-domain-c/ids-vs-tags3.rst
@@ -0,0 +1,19 @@
+.. c:namespace:: ids_vs_tags3
+
+.. c:function:: void f1(int i)
+
+.. c:struct:: f1
+
+	.. c:var:: int i
+
+
+.. c:struct:: f2
+
+	.. c:var:: int i
+
+.. c:function:: void f2(int i)
+
+- :c:var:`f1.i`, resolves to the function parameter
+- :c:var:`struct f1.i`, resolves to struct f1.i
+- :c:var:`f2.i`, resolves to the function parameter
+- :c:var:`struct f2.i`, resolves to struct f2.i
diff --git a/tests/roots/test-domain-c/index.rst b/tests/roots/test-domain-c/index.rst
index 7e2c18be997..4f2a14d6012 100644
--- a/tests/roots/test-domain-c/index.rst
+++ b/tests/roots/test-domain-c/index.rst
@@ -1,3 +1,5 @@
+.. c:namespace:: index
+
 test-domain-c
 =============
 
@@ -8,7 +10,7 @@ directives
 
    :rtype: int
 
-.. c:function:: MyStruct hello2(char *name)
+.. c:function:: struct MyStruct hello2(char *name)
 
    :rtype: MyStruct
 
@@ -46,7 +48,7 @@ directives
 - :c:expr:`unsigned int`
 - :c:texpr:`unsigned int`
 
-.. c:var:: A a
+.. c:var:: struct A a
 
 - :c:expr:`a->b`
 - :c:texpr:`a->b`
diff --git a/tests/roots/test-domain-c/semicolon.rst b/tests/roots/test-domain-c/semicolon.rst
deleted file mode 100644
index 14ba177569d..00000000000
--- a/tests/roots/test-domain-c/semicolon.rst
+++ /dev/null
@@ -1,10 +0,0 @@
-.. c:member:: int member;
-.. c:var:: int var;
-.. c:function:: void f();
-.. .. c:macro:: NO_SEMICOLON;
-.. c:struct:: Struct;
-.. c:union:: Union;
-.. c:enum:: Enum;
-.. c:enumerator:: Enumerator;
-.. c:type:: Type;
-.. c:type:: int TypeDef;
diff --git a/tests/roots/test-domain-c/wrong-tags.rst b/tests/roots/test-domain-c/wrong-tags.rst
new file mode 100644
index 00000000000..5ca56b8a71e
--- /dev/null
+++ b/tests/roots/test-domain-c/wrong-tags.rst
@@ -0,0 +1,14 @@
+.. c:namespace:: wrong_tag
+
+.. c:struct:: A
+
+	.. c:var:: int i
+
+- :c:var:`A.i`
+- :c:var:`union A.i`
+- :c:var:`enum A.i`
+
+.. c:function:: void f1(union A a)
+.. c:function:: void f2(enum A a)
+
+.. c:var:: int union A.j
diff --git a/tests/test_build_html.py b/tests/test_build_html.py
index fccf9cc6aa8..deb978b13c1 100644
--- a/tests/test_build_html.py
+++ b/tests/test_build_html.py
@@ -293,11 +293,11 @@ def test_html4_output(app, status, warning):
         (".//a[@class='reference internal'][@href='#errmod.Error']/strong", 'Error'),
         # C references
         (".//span[@class='pre']", 'CFunction()'),
-        (".//a[@href='#c.Sphinx_DoSomething']", ''),
-        (".//a[@href='#c.SphinxStruct.member']", ''),
-        (".//a[@href='#c.SPHINX_USE_PYTHON']", ''),
-        (".//a[@href='#c.SphinxType']", ''),
-        (".//a[@href='#c.sphinx_global']", ''),
+        (".//a[@href='#C2-Sphinx_DoSomething']", ''),
+        (".//a[@href='#C2-SphinxStruct.member']", ''),
+        (".//a[@href='#C2-SPHINX_USE_PYTHON']", ''),
+        (".//a[@href='#C2-SphinxType']", ''),
+        (".//a[@href='#C2-sphinx_global']", ''),
         # test global TOC created by toctree()
         (".//ul[@class='current']/li[@class='toctree-l1 current']/a[@href='#']",
          'Testing object descriptions'),
diff --git a/tests/test_domain_c.py b/tests/test_domain_c.py
index 2cfcf74faf4..55f2af23063 100644
--- a/tests/test_domain_c.py
+++ b/tests/test_domain_c.py
@@ -32,6 +32,21 @@ class Config:
     return ast
 
 
+def parse_expression(expr, allowTypeExpr=False):
+    class Config:
+        c_id_attributes = ["id_attr"]
+        c_paren_attributes = ["paren_attr"]
+    parser = DefinitionParser(expr, location=None, config=Config())
+    parser.allowFallbackExpressionParsing = False
+    if allowTypeExpr:
+        ast = parser.parse_expression()
+    else:
+        ast = parser._parse_expression()
+        parser.skip_ws()
+    parser.assert_end()
+    return ast
+
+
 def _check(name, input, idDict, output, key, asTextOutput):
     if key is None:
         key = name
@@ -113,14 +128,8 @@ def check(name, input, idDict, output=None, key=None, asTextOutput=None):
 
 
 def test_expressions():
-    def exprCheck(expr, output=None):
-        class Config:
-            c_id_attributes = ["id_attr"]
-            c_paren_attributes = ["paren_attr"]
-        parser = DefinitionParser(expr, location=None, config=Config())
-        parser.allowFallbackExpressionParsing = False
-        ast = parser.parse_expression()
-        parser.assert_end()
+    def exprCheck(expr, output=None, allowTypeExpr=False):
+        ast = parse_expression(expr, allowTypeExpr)
         # first a simple check of the AST
         if output is None:
             output = expr
@@ -141,14 +150,14 @@ class Config:
             raise DefinitionError("")
 
     # type expressions
-    exprCheck('int*')
-    exprCheck('int *const*')
-    exprCheck('int *volatile*')
-    exprCheck('int *restrict*')
-    exprCheck('int *(*)(double)')
-    exprCheck('const int*')
-    exprCheck('__int64')
-    exprCheck('unsigned __int64')
+    exprCheck('int*', allowTypeExpr=True)
+    exprCheck('int *const*', allowTypeExpr=True)
+    exprCheck('int *volatile*', allowTypeExpr=True)
+    exprCheck('int *restrict*', allowTypeExpr=True)
+    exprCheck('int *(*)(double)', allowTypeExpr=True)
+    exprCheck('const int*', allowTypeExpr=True)
+    exprCheck('__int64', allowTypeExpr=True)
+    exprCheck('unsigned __int64', allowTypeExpr=True)
 
     # actual expressions
 
@@ -417,35 +426,65 @@ def test_function_definitions():
     check('function', 'void f(int arr[const static volatile 42])', {1: 'f'},
           output='void f(int arr[static volatile const 42])')
 
+    with pytest.raises(DefinitionError):
+        parse('function', 'void f(int for)')
+
 
 def test_nested_name():
-    check('struct', '{key}.A', {1: "A"})
-    check('struct', '{key}.A.B', {1: "A.B"})
+    check('struct', '{key}.A', {1: "A", 2: "-A"})
+    check('struct', '{key}.A.B', {1: "A.B", 2: "A.-B"})
     check('function', 'void f(.A a)', {1: "f"})
     check('function', 'void f(.A.B a)', {1: "f"})
 
 
 def test_struct_definitions():
-    check('struct', '{key}A', {1: 'A'})
+    check('struct', '{key}A', {1: 'A', 2: '-A'})
 
 
 def test_union_definitions():
-    check('union', '{key}A', {1: 'A'})
+    check('union', '{key}A', {1: 'A', 2: '-A'})
 
 
 def test_enum_definitions():
-    check('enum', '{key}A', {1: 'A'})
+    check('enum', '{key}A', {1: 'A', 2: '-A'})
 
     check('enumerator', '{key}A', {1: 'A'})
     check('enumerator', '{key}A = 42', {1: 'A'})
 
 
 def test_anon_definitions():
-    check('struct', '@a', {1: "@a"}, asTextOutput='struct [anonymous]')
-    check('union', '@a', {1: "@a"}, asTextOutput='union [anonymous]')
-    check('enum', '@a', {1: "@a"}, asTextOutput='enum [anonymous]')
-    check('struct', '@1', {1: "@1"}, asTextOutput='struct [anonymous]')
-    check('struct', '@a.A', {1: "@a.A"}, asTextOutput='struct [anonymous].A')
+    check('struct', '@a', {1: "@a", 2: "-@a"}, asTextOutput='struct [anonymous]')
+    check('union', '@a', {1: "@a", 2: "-@a"}, asTextOutput='union [anonymous]')
+    check('enum', '@a', {1: "@a", 2: "-@a"}, asTextOutput='enum [anonymous]')
+    check('struct', '@1', {1: "@1", 2: "-@1"}, asTextOutput='struct [anonymous]')
+    check('struct', '@a.A', {1: "@a.A", 2: "@a.-A"}, asTextOutput='struct [anonymous].A')
+
+
+def test_tagged_names():
+    for key in ('struct', 'union', 'enum'):
+        with pytest.raises(DefinitionError):
+            parse('member', "int {} A".format(key))
+        with pytest.raises(DefinitionError):
+            parse('function', "int {} A()".format(key))
+        with pytest.raises(DefinitionError):
+            parse('function', "int A(int {} a)".format(key))
+        for objType in ('macro', 'struct', 'union', 'enum', 'enumerator'):
+            with pytest.raises(DefinitionError):
+                parse(objType, '{} A'.format(key))
+        # type
+        with pytest.raises(DefinitionError):
+            parse('type', '{} A'.format(key))
+        check('type', '{key1}{key2} A A'.format(key2=key, key1="{key}"), idDict={1: 'A'}, key='typedef')
+        # TODO: namespace, namespace-push, namespace-pop
+        # TODO: alias
+        # primary expression
+        for expr in ('{} a.b', 'a.{} b.c', 'a.{} b'):
+            with pytest.raises(DefinitionError):
+                parse_expression(expr.format(key))
+        # postfix expression
+        for expr in ('a->{} b->c', 'a->{} b'):
+            with pytest.raises(DefinitionError):
+                parse_expression(expr.format(key))
 
 
 def test_initializers():
@@ -523,8 +562,15 @@ def test_attributes():
 #     raise DefinitionError("")
 
 
+def split_warnigns(warning):
+    ws = warning.getvalue().split("\n")
+    assert len(ws) >= 1
+    assert ws[-1] == ""
+    return ws[:-1]
+
+
 def filter_warnings(warning, file):
-    lines = warning.getvalue().split("\n")
+    lines = split_warnigns(warning)
     res = [l for l in lines if "domain-c" in l and "{}.rst".format(file) in l and
            "WARNING: document isn't included in any toctree" not in l]
     print("Filtered warnings for file '{}':".format(file))
@@ -579,9 +625,155 @@ def test_build_domain_c_anon_dup_decl(app, status, warning):
 
 
 @pytest.mark.sphinx(testroot='domain-c', confoverrides={'nitpicky': True})
-def test_build_domain_c_semicolon(app, status, warning):
+def test_ids_vs_tags0(app, status, warning):
+    # this test is essentially the base case for the intersphinx tests,
+    # where both the primary declarations and the references are in one project
+    app.builder.build_all()
+    ws = filter_warnings(warning, "ids-vs-tags0")
+    assert len(ws) == 3
+    msg = "WARNING: c:identifier reference has incorrect tagging:"
+    msg += " Full reference name is '{}'."
+    msg += " Full found name is '{}'."
+    assert msg.format("_struct", "struct _struct") in ws[0]
+    assert msg.format("_union", "union _union") in ws[1]
+    assert msg.format("_enum", "enum _enum") in ws[2]
+
+
+@pytest.mark.sphinx(testroot='domain-c', confoverrides={'nitpicky': True})
+def test_ids_vs_tags1(app, warning):
+    app.builder.build_all()
+    ws = filter_warnings(warning, "ids-vs-tags1")
+    assert len(ws) == 0
+    t = (app.outdir / "ids-vs-tags1.html").read_text()
+    lis = [l for l in t.split('\n') if l.startswith("<li")]
+    entries = []
+    for l in lis:
+        li = ElementTree.fromstring(l)
+        assert li.tag == 'li'
+        assert len(li) == 1
+        p = li[0]
+        assert p.tag == 'p'
+        assert len(p) == 1
+        a = p[0]
+        assert a.tag == 'a'
+        target = a.attrib['href'].lstrip('#')
+        title = a.attrib['title']
+        assert len(a) == 1
+        code = a[0]
+        assert code.tag == 'code'
+        text = ''.join(code.itertext())
+        entries.append((target, title, text))
+    expected = []
+    idPrefix = 'C2-ids_vs_tags.'
+    for tag in ['struct', 'union', 'enum']:
+        name = 'f_' + tag
+        tagTitle = tag + ' ' + name
+        title = name
+        tagTarget = idPrefix + '-' + name
+        target = idPrefix + name
+        # using the designated role
+        expected.append((tagTarget, tagTitle, title))
+        expected.append((tagTarget, tagTitle, tagTitle))
+        # using :c:type:
+        expected.append((target, title, title))
+        expected.append((tagTarget, tagTitle, tagTitle))
+        # using :any:
+        expected.append((target, title, title))
+        expected.append((tagTarget, tagTitle, tagTitle))
+    assert entries == expected
+
+
+@pytest.mark.sphinx(testroot='domain-c', confoverrides={'nitpicky': True})
+def test_ids_vs_tags2(app, warning):
     app.builder.build_all()
-    ws = filter_warnings(warning, "semicolon")
+    ws = filter_warnings(warning, "ids-vs-tags2")
+    assert len(ws) == 0
+
+
+@pytest.mark.sphinx(testroot='domain-c', confoverrides={'nitpicky': True})
+def test_ids_vs_tags3(app, warning):
+    app.builder.build_all()
+    ws = filter_warnings(warning, "ids-vs-tags3")
+    assert len(ws) == 0
+    t = (app.outdir / "ids-vs-tags3.html").read_text()
+    lis = [l for l in t.split('\n') if l.startswith("<li")]
+    entries = []
+    for l in lis:
+        li = ElementTree.fromstring(l)
+        assert li.tag == 'li'
+        assert len(li) == 1
+        p = li[0]
+        assert p.tag == 'p'
+        assert len(p) == 1
+        a = p[0]
+        assert a.tag == 'a'
+        target = a.attrib['href'].lstrip('#')
+        title = a.attrib['title']
+        assert len(a) == 1
+        code = a[0]
+        assert code.tag == 'code'
+        text = ''.join(code.itertext())
+        entries.append((target, title, text))
+    idPrefix = 'C2-ids_vs_tags3.'
+    expected = [
+        (idPrefix + 'f1', 'f1.i', 'f1.i'),
+        (idPrefix + '-f1.i', 'struct f1.i', 'struct f1.i'),
+        (idPrefix + 'f2', 'f2.i', 'f2.i'),
+        (idPrefix + '-f2.i', 'struct f2.i', 'struct f2.i'),
+    ]
+    assert entries == expected
+
+
+def test_duplicate_tags(app, warning):
+    text = """
+.. c:struct:: A
+.. c:union:: A
+.. c:enum:: A
+"""
+    restructuredtext.parse(app, text)
+    ws = split_warnigns(warning)
+    assert len(ws) == 4
+    assert "index.rst:3: WARNING: Duplicate C declaration" in ws[0]
+    assert "Declaration is '.. c:union:: A'." in ws[1]
+    assert "index.rst:4: WARNING: Duplicate C declaration" in ws[2]
+    assert "Declaration is '.. c:enum:: A'." in ws[3]
+
+
+@pytest.mark.sphinx(testroot='domain-c', confoverrides={'nitpicky': True})
+def test_build_domain_c_wrong_tags(app, warning):
+    app.builder.build_all()
+    ws = filter_warnings(warning, "wrong-tags")
+    template = ".rst:%d: WARNING: c:%s reference uses wrong tag:"\
+               " reference name is '%s' but found name is '%s'."\
+               " Full reference name is '%s'."\
+               " Full found name is '%s'."
+    expected = [
+        template % (8, 'var', 'union A', 'struct A', 'union A.i', 'wrong_tag.struct A.i'),
+        template % (9, 'var', 'enum A', 'struct A', 'enum A.i', 'wrong_tag.struct A.i'),
+        template % (11, 'identifier', 'union A', 'struct A', 'union A', 'wrong_tag.struct A'),
+        template % (13, 'identifier', 'enum A', 'struct A', 'enum A', 'wrong_tag.struct A'),
+        template % (14, 'identifier', 'union A', 'struct A', 'union A', 'wrong_tag.struct A'),
+    ]
+    for i in range(len(expected)):
+        assert expected[i] in ws[i]
+    assert len(ws) == len(expected)
+
+
+def test_build_domain_c_semicolon(app, warning):
+    text = """
+.. c:member:: int member;
+.. c:var:: int var;
+.. c:function:: void f();
+.. .. c:macro:: NO_SEMICOLON;
+.. c:struct:: Struct;
+.. c:union:: Union;
+.. c:enum:: Enum;
+.. c:enumerator:: Enumerator;
+.. c:type:: Type;
+.. c:type:: int TypeDef;
+"""
+    restructuredtext.parse(app, text)
+    ws = split_warnigns(warning)
     assert len(ws) == 0
 
 
@@ -593,8 +785,8 @@ def test_build_function_param_target(app, warning):
     assert len(ws) == 0
     entries = extract_role_links(app, "function_param_target.html")
     assert entries == [
-        ('c.f', 'i', 'i'),
-        ('c.f', 'f.i', 'f.i'),
+        ('C2-function_param_target.f', 'i', 'i'),
+        ('C2-function_param_target.f', 'f.i', 'f.i'),
     ]
 
 
@@ -621,7 +813,7 @@ def test_cfunction(app):
                 domain="c", objtype="function", noindex=False)
 
     entry = _get_obj(app, 'PyType_GenericAlloc')
-    assert entry == ('index', 'c.PyType_GenericAlloc', 'function')
+    assert entry == ('index', 'C2-PyType_GenericAlloc', 'function')
 
 
 def test_cmember(app):
@@ -631,7 +823,7 @@ def test_cmember(app):
                 domain="c", objtype="member", noindex=False)
 
     entry = _get_obj(app, 'PyTypeObject.tp_bases')
-    assert entry == ('index', 'c.PyTypeObject.tp_bases', 'member')
+    assert entry == ('index', 'C2-PyTypeObject.tp_bases', 'member')
 
 
 def test_cvar(app):
@@ -641,7 +833,7 @@ def test_cvar(app):
                 domain="c", objtype="var", noindex=False)
 
     entry = _get_obj(app, 'PyClass_Type')
-    assert entry == ('index', 'c.PyClass_Type', 'member')
+    assert entry == ('index', 'C2-PyClass_Type', 'member')
 
 
 def test_noindexentry(app):
@@ -650,18 +842,25 @@ def test_noindexentry(app):
             "   :noindexentry:\n")
     doctree = restructuredtext.parse(app, text)
     assert_node(doctree, (addnodes.index, desc, addnodes.index, desc))
-    assert_node(doctree[0], addnodes.index, entries=[('single', 'f (C function)', 'c.f', '', None)])
+    assert_node(doctree[0], addnodes.index, entries=[('single', 'f (C function)', 'C2-f', '', None)])
     assert_node(doctree[2], addnodes.index, entries=[])
 
 
 @pytest.mark.sphinx(testroot='domain-c-intersphinx', confoverrides={'nitpicky': True})
-def test_intersphinx(tempdir, app, status, warning):
+def test_intersphinx_v3_remote(tempdir, app, status, warning):
+    # a splitting of test_ids_vs_tags0 into the primary directives in a remote project,
+    # and then the references in the test project
     origSource = """\
 .. c:member:: int _member
 .. c:var:: int _var
 .. c:function:: void _function()
 .. c:macro:: _macro
 .. c:struct:: _struct
+
+	.. c:union:: @anon
+
+		.. c:var:: int i
+
 .. c:union:: _union
 .. c:enum:: _enum
 
@@ -686,6 +885,8 @@ def test_intersphinx(tempdir, app, status, warning):
 _macro c:macro 1 index.html#c.$ -
 _member c:member 1 index.html#c.$ -
 _struct c:struct 1 index.html#c.$ -
+_struct.@anon c:union 1 index.html#c.$ _struct.[anonymous]
+_struct.@anon.i c:member 1 index.html#c.$ _struct.[anonymous].i
 _type c:type 1 index.html#c.$ -
 _union c:union 1 index.html#c.$ -
 _var c:member 1 index.html#c.$ -
@@ -701,3 +902,61 @@ def test_intersphinx(tempdir, app, status, warning):
     app.builder.build_all()
     ws = filter_warnings(warning, "index")
     assert len(ws) == 0
+
+
+@pytest.mark.sphinx(testroot='domain-c-intersphinx', confoverrides={'nitpicky': True})
+def test_intersphinx_v4_remote(tempdir, app, status, warning):
+    # a splitting of test_ids_vs_tags0 into the primary directives in a remote project,
+    # and then the references in the test project
+    origSource = """\
+.. c:member:: int _member
+.. c:var:: int _var
+.. c:function:: void _function()
+.. c:macro:: _macro
+.. c:struct:: _struct
+
+	.. c:union:: @anon
+
+		.. c:var:: int i
+
+.. c:union:: _union
+.. c:enum:: _enum
+
+    .. c:enumerator:: _enumerator
+
+.. c:type:: _type
+.. c:function:: void _functionParam(int param)
+"""  # noqa
+    inv_file = tempdir / 'inventory'
+    inv_file.write_bytes(b'''\
+# Sphinx inventory version 2
+# Project: C Intersphinx Test
+# Version: 
+# The remainder of this file is compressed using zlib.
+''' + zlib.compress(b'''\
+_enumerator c:enumerator 1 index.html#C2--_enum.$ -
+_function c:function 1 index.html#C2-$ -
+_functionParam c:function 1 index.html#C2-$ -
+_functionParam.param c:functionParam 1 index.html#C2-_functionParam -
+_macro c:macro 1 index.html#C2-$ -
+_member c:member 1 index.html#C2-$ -
+_type c:type 1 index.html#C2-$ -
+_var c:member 1 index.html#C2-$ -
+enum _enum c:enum 1 index.html#C2--_enum -
+enum _enum._enumerator c:enumerator 1 index.html#C2--_enum._enumerator -
+struct _struct c:struct 1 index.html#C2--_struct -
+struct _struct.union @anon c:union 1 index.html#C2--_struct.-@anon struct _struct.union [anonymous]
+struct _struct.union @anon.i c:member 1 index.html#C2--_struct.-@anon.i struct _struct.union [anonymous].i
+union _union c:union 1 index.html#C2--_union -
+'''))  # noqa
+    app.config.intersphinx_mapping = {
+        'https://localhost/intersphinx/c/': inv_file,
+    }
+    app.config.intersphinx_cache_limit = 0
+    # load the inventory and check if it's done correctly
+    normalize_intersphinx_mapping(app, app.config)
+    load_mappings(app)
+
+    app.builder.build_all()
+    ws = filter_warnings(warning, "index")
+    assert len(ws) == 0